str="asdyzcbnp13456yyaswsedyvbunhj"
print(str[:(len(str))-11:-1])




#三种方法去重
list1=[]#第一种
for i in str:

    if i in list1:
        list1.remove(i)
    else:
        list1.append(i)
for u in str:
    if u not in list1:
        list1.append(u)
print(list1)

#第二种
set1=set(str)
print(set1)
#第三种
result={}
for s in str:
    result[s]=str.count(s)
print(result.keys())